Assionor to the holt



E. E. WICKERSHAM.

SPEED GOVERNOR. v APPLICATION FILED MAR.20. 1917.

1,381,778. Pmmmne 14, 1921.

2 SIHEETS-SHEET WITNESSES: IN "ENTOR M M 2717192 27 Wic/knsfiam UNITED STATES PATENT OFFICE.

ELMER E. WICKERSHAM, OF SUNNYVALE, CALIFORNIA, ASSIGNOR TO THE HOLT MANUFACTURING- COMPANY, OF STOCKTON, CALIFORNIA, A CORPORATION OF CALIFORNIA.

SPEED-GOVERNOR.

Patented June 14, 1921.

Application filed March 20, 1917. Serial No. 155,970.

To all whom it may concern: I

Be it known that I, ELMER E. WICKER- SHAM, a citizen of the United States, residing at Sunnyvale, in the county of Santa Clara and State of California, have invented new and useful Improvements in Speed- Governors, of which the following is a specification.

This invention relates to speed governors for engines; and has for its object to provide for a more accurate governing of the speed of the engines, so that a slight increase in speed, beyond the maximum provided for by the adjustment of the governor, will cause the governor to respond quickly and close the throttle of the engine and instantly check the speed. 7

On gas engines for tractors and other heavy duty purposes it is necessary to have an open throttle, when the engine 1s operating at a comparatively high rate of speed, in order to allow for suflicient driving power of the engine under maximum load. The

governor, therefore, is adjusted so as not to begin the performance of its throttling action until the maximum speed allowed for is passed. Therefore, when theclutchcs on the tractor drive are suddenly thrown out, the speed of the engine is accelerated, but the governor being slow to respond as heretofore constructed a speed is attained which is very injurious to the parts before the throttle is acted upon sufliciently by the governor to check the speed.

.With my invention it is possible to so set the governor that the maximum operating speed will be permitted without any throttling action, but any slight increase beyond such speed will cause the governor to instantly close the throttle.

This object is attained by providing a rotatable member carrying a centrifugal device normally held with its weighted end inward by an adjusting spring, and carrying at its opposite end an adiustable block or setscrew to engage a friction shoe movable against a friction disk, whereby to rotate the latter. said disk being connected with the throttle to close the latter on being rotated.

One form which my invention may assume is exemplified in the following description and illustrated in the accompanying drawings. in which Figure 2 shows a plan view of an engine equipped with a speed governor embodying my invention.

Fig. 1 shows an elevation of the manifold side of such engine.

Fig. shows a plan view of a governor embodying my invention, the cover of the caslng being removed.

Fig. 41 shows a vertical, sectional view of the device shown in Fig. 3.

Fig. 5 is a view illustrating the connection for a horlzontally arranged governor.

In the form of my invention illustrated herewith, a conventional type of internal combustion engine is shown, the cam shaft or other rotatable element of which carries the governor, the latter comprising a casing 10, within which is pivoted a weighted lever 11, the lever being preferably curved to fit the circular casing. The lever 11, adjacent to its p vot 12 and toward the weighted end, 1s provlded with a series of notches 13, and the rim portion 14 of the casing has similar notches 15, between which is carried an expansible leaf spring 16 tending to hold the weighted end of the lever inwardly. The short end of the lever, opposite to the we ghted end, carries a set-screw 17, or other ad ustable device, preferably operable from the exterior of the casing throughan opening 18 in the rim of the casing, which openmg is normally closed by a plug 19. i

In the path of the set-screw 17 is a friction shoe 20, held in place by a lug 21 formed on the'interior of the casing, said shoe being movable, bodily, on the lug toward and from the center of the casing. A friction disk 22 1s journaled in a cover 23 of the casing by means of a spindle 24 rotatable in a bearing 25, said disk being so positioned as to be engaged by the shoe when the latter is moved lnwardly by the centrifugal action of the weighted lever 11. The shoe 20 has a curvature corresponding with the contour of the disk 22 and being movable bodily on the lug 21 will engage throughout ts surfacewith the peripherv of the disk so as to insure a maximum of frictional contact for driving the latter.

The spindle 24 carries a crank arm 26, which is connected to the throttle of the engine in any suitable manner so that the latter will be closed when the arm is moved by the rotation of the disk. The rotation of the casing, and consequently of the shoe, will,

when the latter is contacted with the disk, rotate said disk and thereby turn the arm 26 in a direction to close the throttle of the engine. In the present instance I have shown the arm 26 connected to a link 27, the latter in turn connected to one end of a bell-crank lever 27. To the opposite end of the bellcrank lever is connected a link 28 running to the throttle of the earbureter 29, and a link 30 is connected to the same side of the bellcrank lever and extends to the operators control lever not shown.

Preferably I provide a pressure spring 31 for the bell-crank lever to retain the latter in position where the thrott e will be held open. This spring is light in its operation and the governor action being more or less direct and positive the responsiveness of the latter will not be interfered with by the spring.

By changing the adjustment of the leaf spring. 16 I can set the governor for any desired speed limit and by means of the set screw 17, adjustable from without the casing, I can vary the action of the governor as may be desired.

Numerous tests conducted with this governor have shown it to be exceedingly responsive and accurate and the reason for this will be seen from the fact that a very slight pressure of the shoe against the disk is all that is required to operate the throttle. This pres sure does not occur until the weighted lever has been thrown out beyond the maximum position allowed for by the adjustment and there is, therefore, not even a tendency to move the throttle until the maximum speed limit is passed.

It is obvious that the parts can be so adjusted that a slight outward movement of the centrifugal device beyond the maximum point allowed for will supply the necessary pressure of the shoe against the disk, whereby to throttle the engine.

The important factor of a device of this kind is that the throttling action be not too slow or cumbersome but shall occur instantly and at whatever point the governor is set for. The difference in pressure of the shoe against the disk required for a slight throttling action and that required for a full closing of the throttling is obviously slight, so that the latter result is not delayed as in prior devices.

While I have shown and described but one form of my invention herein, it will be understood, nevertheless, that the same is susceptible of modifications and that various changes in the construction and arrangement of the several parts may be employed without departing from the spirit of the invention as disclosed in the appended claims.

Having thus described my invention, What I claim and desire to secure by Letters Patent is- 1. A speed governor, comprising a rotatable casing, a centrifugal lever pivoted thereon, a friction shoe carried by the casing and controlled by said lever, and a disk j ournaled in said casing and engageable by the shoe to receive motion therefrom.

2. A speed governor, comprising a rotatable casing, a centrifugal lever pivoted thereon, a friction shoe carried by the casing and controlled by said lever, a disk journaled in said casing and engageable by the shoe to receive motion therefrom, and an adjustable spring between said lever and casing for varying the centrifugal movement of the lever.

3. A speed governor, comprising a rotatable casing, a centrifugal lever pivoted thereon, a friction shoe carried by the casing and controlled by said lever, a disk journaled in said casing and engageable by the shoe to receive motion therefrom, and an adjustable block on the inwardly moving end of said lever to engage with the shoe.

l. A speed governor, comprising a rotatable casing, a centrifugal lever pivoted thereon, a friction shoe carried by the casing and controlled by said lever, a disk journaled in said casing and engageable by the shoe to receive motion therefrom, and a lug on the casing to support said shoe, said shoe being movable bodily towardand from the disk and curved to fit the contour of the same.

A speed governor, comprising a rotatable casing, a centrifugal lever carried in said casing, a shoe carried by said casing, a disk journaled centrally in said casing and adapted to be engaged by the shoe to receive motion therefrom, and a set-screw on the inwardly moving end of said lever to engage with the shoe, said casing being provided with an opening to permit the adjustment of the set-screw from without.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

ELMER- E. IVICKERSHAM.

lVitnesses:

JOHN II. HnnRiNe,

W. W. HnALn-Y. 

